[Primary hyperparathyroidism in children]

BACKGROUND

 Primary hyperparathyroidism (PHPT) is an endocrine disorder characterized by excessive secretion of parathyroid hormone (PTH) with upper-normal or elevated blood calcium levels due to primary thyroid gland pathology. PHPT is a rare pathology in children, with a prevalence of 2-5:100,000 children according to the literature. Due to the non-specificity of clinical manifestations at onset (nausea, vomiting, abdominal pain, emotional lability), the disease may remain undiagnosed for a long time.

AIM

 To study the features of the course and molecular genetic basis of primary hyperparathyroidism in children.

MATERIALS AND METHODS

 Retrospective observational study of 49 patients diagnosed with primary hyperparathyroidism. All patients underwent a comprehensive laboratory-instrumental and molecular genetic study at the Institute of Pediatric Endocrinology, Endocrinology Research Center of Russia in the period 2014-2022.

RESULTS

 The first clinical symptoms of PHPT were noted at the age of 13.8 years [10.6; 1 5.2], among which fatigue, headaches, dyspepsia, lower limb pain, and fractures were the most common. The age of diagnosis was 15.81 years [13.1; 16.8], all children were found to have high levels of PTH, total and ionized calcium, with hypophosphatemia in 93.9% of patients (n=46) and hypercalciuria in 43% (n=21). Five out of 49 patients (10.2%) were found to have ectopy of the thyroid: 3 showed an intrathyroidal location, 2 in the mediastinal region. Molecular genetic study revealed mutations in 32.7% of patients (n=16, CI (21; 47)), mutations in MEN1 being the most frequent (n=11). Pathogenic variants in CDC73 were detected in 3 patients, RET - in 2. Among the operated 39 patients, adenoma of the thyroid was detected in 84.6% of cases (n=33), hyperplasia in 7.7% (n=3), atypical adenoma in 5.1% (n=2), carcinoma in 5.1% of cases (n=2).

CONCLUSION

 The paper presents the peculiarities of the course and the results of molecular genetic study of pediatric PHPT. This sample is the largest among those published in the Russian Federation.

Arterial blood supply of the internal neck organs: anatomy, topography, clinical significance in endocrine surgery

BACKGROUND. Current trends of «fast track surgery» give rise to development of new safe techniques of the thyroid and parathyroid surgery, the purpose of which is to minimize the level of postoperative complications, such as vocal cord palsy, hypoparathyroidism, bleeding. In this regard, it is important for the endocrine surgeon to save «dry operating field», which contributes to the clear visualization of such «thin» structures as the recurrent laryngeal nerve, the external branch of the superior laryngeal nerve and the parathyroid glands. Therefore, the key issue of this surgery is to understand the anatomical and topographic features of the blood supply to the internal neck organs (a complex of neck organs consisting of the thyroid and parathyroid glands, larynx, trachea, esophagus).

AIM. To determine the main sources of arterial blood supply of the internal neck organs and their anatomical, topographic features.

MATERIALS AND METHODS. The computed tomography protocols of cervical branches of brachiocephalic arteries were analysed in the study. The thickness of the reconstructed sections in the axial, frontal and sagittal planes was 0.35±0.05 mm. The fact of blood supply was confirmed by the anatomical close of the arterial structure to the internal organ and the presence of intramural arterial branches.

RESULTS. The course of all cervical branches of the subclavian and common carotid artery was traced among 42 patients. It is noted, that only the inferior, superior thyroid arteries and thyroid ima artery supply internal neck organs with the blood. At the same time, the superior thyroid artery was visualized in all angiograms. However, the inferior thyroid artery was absent in 2.4% of cases. The thyroid ima artery was rarely detected (in 4.8% of patients). In 73.2% of cases, the inferior thyroid artery was detected high at the upper third level of the thyroid lobe and then had a descending course. In 23.2% of cases, the artery was formed at the middle third level of the thyroid lobe and was directed horizontally to the gland. Only in 3.6% of cases, the ascending course was determined in the vessel. The inferior thyroid artery was located on the posterior surface of the thyroid lobe, where it formed glandular branches. On the contrary, the branches of the superior thyroid artery were located mainly along the anterolateral surface of the thyroid gland. The average thickness of the inferior thyroid artery was 2.1±0.5 mm, and the superior thyroid artery was 1.6± 0.7 mm.

CONCLUSION. According to the study, arterial blood supply to the internal neck organs is provided mainly by the inferior and superior thyroid arteries. At the same time, the trunk of the inferior thyroid artery is larger than the superior thyroid artery (p=0.032). The inferior thyroid artery forms branches along the posterior surface of the thyroid lobe and from a topographic point of view it is the main source of blood supply to the parathyroid glands. In most cases, the inferior thyroid artery has a descending course, is directed along the posterior surface of the thyroid gland and forms an X-shaped intersection with the recurrent laryngeal nerve.

Modern problems of hyper- and hypoparathyroidism

The parathyroid glands are the most important regulators of mineral metabolism. The parathyroid glands were first discovered only in 1880 and their function went the long way unrecognized. Even the term "parathyroid gland" itself speaks of the initial misconception of it as an underdeveloped part of the thyroid. To date, there is a large amount of data regarding the role of this endocrine gland in the human body and the significant changes associated with their dysfunction, including such widespread diseases such primary, secondary and tertiary hyperparathyroidism, hypoparathyroidism. This review covers the problem of the main disturbances in calcium-phosphorus metabolism, presents the results of databases of patients with primary hyperparathyroidism and hypoparathyroidism, as well as current epidemiological trends in Russia and in the world.

[Neuroendocrine markers in parathyroid tumors]

The parathyroid glands (PTGs) are a key regulator of calcium and phosphorus metabolism in the human body. In terms of their, morphological and immunophenotypic characteristics, PTGs are neuroendocrine organs, and their neoplasms are neuroendocrine tumors. These neoplasms include adenoma and cancer; in addition, glandular hyperplasia may develop, which is most characteristic of multiple endocrine neoplasia (MEN1, MEN2a, and MEN4) syndromes. The morphological characteristics of pathologically altered PTGs in MEN syndromes are variable. The analysis and generalization of knowledge about the features and expression of various immunohistochemical markers in PTG tissue in health and in diseases are useful in the practical work of not only pathologists, but also clinicians of various specialties.